Flotation apparatus



June 3, 1930. J P; RUTH, JR 1,760,916

FLOTATIION APPARATUS Filed March e, 1928 2 Sheets-Sheet 1 by v Jade 41% 2 azz, /7:

June 3, 1930. I J. RUTH, JR I 1,760,916

FLOTAT I ON APPARATUS Filed March 26, 1928 2 Sheets-Sheet 2 elk-fox u 21 Patented June 3, 1930 UNITED STATES JOSEPH P. RUTH, JR, 01 DENVER, COLQRACDO FLOTATION' APPARATUS Application .flled March as, 1928. Serial No. 264,798.

particularly to an improved cell construction.

to be used in the combination shown and de- 5 scribed in my copending application Serial N 0. 253,978, filed February 28, 1928.

In the application above identified, I have shown and claimed an arrangement of flotation cells in which the cells are divided into a roughing group, a cleaning group and a finishing group, and in which the cells are also so arranged that no two cells are on the same level but are each located at a higher level than the one directly beneath so that from the cells of the roughing group to the cells of the cleaning group and from the cells of the cleaning group to the finishing cell. In this way a much more convenient lay-out is obtained and a large amount of powed is saved.

In the application above identified, I have shown and described one particular construction of flotation cell which is adapted to be used in the combination described and claimed.

It is the object of this invention to produce an improved form of flotation cell which shallbe so constructed that it shall be particularly well adapted for use in the combina tion referred to in the application above identified.

In order to most clearly describe the present invention, it has'been illustrated on the accompanying drawings to which reference will now be had and in which:

Fig. 1 is a side elevation showing a series of cells arranged in three groups and sb related to each other that the pulp will flow upwardly from a lower to a higher cell of each group and the froth will flow downwardly from the uppermost group to the lowermost cell of the next group below and from the cells of this intermediate group to the finishing cell; I

Fig. 2 is a view looking downwardly onto the froth launder showing the manner. in which the same is partitioned;

Fig. 3 is a side elevation of one of the improved flotation cells, parts thereof being the froth will flow by the action of gravity shown insection so as'to better disclose the construction Fig. 4 is a section taken on line H, F ig. 3.;

Fig. 5. is a side elevation showing two adjacent cells and the manner in which the pulp conduit extends from the lower cell to the one drectlyabove, parts of these cells have been removed so as to betterdisc'lose the construction Fig. 6 is a section taken on line 6-6, Fig. 5; and

Fig. 7 is aplan view partly in section taken on'line 7'7, Fig. 6.

In'Fig. 1 numeral 1 indicates a support which may be formed of concrete or any other suitable material and which is pro-- vided with a plurality of steps which have been indicated b numeral 2. These steps are preferably 0 the same width and each differing in height from the adjacent step by a certain amount. Located on each of these steps is a flotation cell which has been indicated in its entirety by numeral 8. These cells are arranged in three groups, A, B and G. I Group A contains eight cells and will be referred to hereinafter as -the roughing group. Group B contains three cells and willbe referred to as the cleaning group, while groupC has been shown as consisting of a single cell and constitutes the finishing group. The number of cells in each group can' differ from the number shown in the drawings and I do not want to be limited in any way tothe specific number of cells emlploved in each of the groups.

11 Figs. 5 and 6, I have shownone construction of cell suitable for use in this/combination. This cell consists of a bottom 4 and rear wall 5, a front wall 6, side walls 7 and 8 and a partition wall 9. The partition wall 9 divides the cell into two parts, one of which has been designated by D and the other by E. That part designated by letter D forms the feed box into which the pulp is delivered and the part designated by numeral E, the agitation box or chamber in which the impeller 10 is located. This impeller is secured to the lower end of the shaft 11 that is mounted for rotation in bearings 12 and 13 and which is rotated at a high speed by means of a motor 14 that is connected to the shaft by means of belts 15. Bearing 12 is secured to an angle iron 16, while bearing 13 is secured to a base 17 supported on the flanges of channels 18. Located directly above the impeller 10 is a checker work box having right angularly related partitions 19 and 20, which form square openings 21 like those. shown in Fig. 7 These openings serve to prevent rotary motion of the ulp' and to give it.an upward direction. located directly beneath the impeller 10, is a bottom or transverse partition 22, that is provided with a central opening 23 which is in communication with the interior of feed box D, so that the pulp mayflow from the feed box into the impeller chamber in the direction indicated by the arrow. Secured to the upper edge of the partition 9 is a froth overflow chute 24, which directs the froth into the launder 25. This launder has vertical side members 26 and a bottom member 27, and will be hereinafter more fully described. Referring now more particularly to Fig. 5 it will be seen that adiving board 28 extends downwardly a short distance from the inner surface of side 8 and forms a passage through which the pulp may flow into the pulp chute 29,,that is attached to the upper edge of side Wall 8 in the manner shown. The level at which the pulp overflows from the agitating compartment into the pulp chute can be varied by adding or removing transverse bars like those indicated by numeral 30. The diving board 28 keeps the froth from flowing over into the chute 29 and as the froth is much lighter than the pulp, it will float on top of the latter and will overflow through the froth chute 24. The pulp level or line of demarcation between the froth and the pulp has been indicated by a dotted line. From the pulp chute. 29, a tubular conduit 31 extends to the feed box of the next hi her cell in the manner shown in Fig. 5. hen the impeller is rotatin and pulp is fed to the lowermost cell 0 the roughing group through hopper 32, it will be sucked from the feed box by the action of the impeller and the froth will flow through the froth chute into the launder 25 and the pulp will flow into the pulp conduit 29 and thence to the next higher cell where this 0 eration will be repeated. In the example il ustrated, the

pulp is subjected to eight separate treatments in the roughing group and is delivered by the uppermost cell of this group into a launder 33, which conveys it to a dump. The froth from all of the cells in the roughing group is delivered to the froth launder and flows'downwardly until it strikes the partition 34 which is placed directly below an.

opening 35 that is located above the feed box of the lowermost cellin the cleaning group. The froth after it is delivered to the lowermost cell of the cleaning group is transferred by means ofan impeller from the feed box to the frothing chamber and the froth from these cells is delivered into the compartment 36 of the launder while the pulp is transferred in an upward direction from the lowermost cell of the cleaning group to the uppermost cell of the roughing group where it is delivered to the launder 33 that carries it to the dump. The froth from the three cells of the cleaning group flows downwardly until it strikes the partition 37 and passes thence through opening 38 into the feed box of the finishing cell. The froth from the finishing cell is delivered into the compartment 39 of the launder and passes from there to the storage bin from which it is delivered to the smelter. From the above it will be ,seen that after the pulp has been delivered into the hopper 32, it will not have to be pumped by means of auxiliary pumps but will be transferred in an upward direction through the action of the impellers and the froth will flow downwardly by the action of gravity, thereby producing a continuous operation in which the material is subjected to the minimum amount of handling and therefore the treatment to which the pulp is subjected can be accomplished at minimum cost.

In Figs. 3 and 4 I have shown a slightly modified form of construction in which the impeller 10 is located directly above the bottom 4, and in which the impeller shaft 11 passes throu h a tubular member 40. The pulp from t e feed box D is delivered to the impeller through a conduit 41. The pulp follows the direction of the arrows and passes upwardly between the periphery of the top 42 and the inside of the frothing chamber E as shown by the arrows in Fig. 4. In other respects than those enumerated, this construction is substantially the same as that shown in Figs. 5 and 6 and cells of this construction can be substituted in the combination illustrated in Fig. 1 and will operate in the same manner as above described.

From the above description it will be apparent that I have shown two specific types of cells that are especially well adapted for use in my improved combination and it is also apparent that cells constructed in a different manner than those described, but which employ an impeller for the purpose of raising the level of the pulp in the frothing chamber, can also be employed as the important feature of the construction for this purpose is that the level of the pulp in the frothing chamber must be maintained, during operation, at a higher point than the level of the pulp in the feed box and therefore any cell that conforms to this can be employed for this purpose.

It is evident that if the impeller is stopped during operation the level of the liquid in the frothing chamber will fall and the level of the liquid in the feed box vwil'lzrise until they become equal. It is therefore necessary that the capacity of the feed box shall be large enough to contain the extra pulp that will enter it and for this reason the capacity of the frothing compartment must be less than twice the capacity of the feed box. As the liquid level in the feed box never falls below that indicated by the dotted lines the capacities referred to are then above the lower level of the pulp in the feed box.

Having described the invention what is claimed as new is i 1. A flotation device comprising a plurality of cells, each of which is located at a different level and adapted to feed one into another by gravity, each of said cells having a feed box and a frothing compartment, said box and compartment being joined by a passageway, an impeller in said passageway, the frothing compartment having a froth overflow on the same side as the feed box and above it, the side of the frothing compartment adjacent the next higher cell being provided with a pulp overflow, a chute located beneath the pul overflow and in communication with the Feed boxof the next higher cell, and an inclined launder located beneath the froth overflows of the cells and above the feed boxes.

2. A flotation apparatus comprising a plurality of units each of which is located at a dilferent level and adapted to feed into one another by the action'of gravity, each unit consisting of a tank, an agitator within the tank, said tank having a froth overflow and a tailings overflow below the froth overflow, a feed box below the froth overflow, a conduit from the feed box to the tank, the entrance to the feed box being below the level of the tailings overflow of the adjacent unit which is located at a lower level and an inclined launder positioned beneath the froth overflows of the several units and above the feed boxes.

3.'A froth flotation separation apparatus comprising a cell having a combined agitating, gasifying and froth separating chamber, an inlet passage provided with means for cascading the pulp therein and having an inlet entering the chamber, a bathe in the chamber, an agitator in the lower part of the chamber adjacent the inlet and below the baflie and arranged to exert suction on the pulp to draw the pulp through the inlet and force the pulp upwardly through the cha nber. whereby the bubbles may rise directly upwardly from the zone of agitation to a froth overflow, anoverflow for tailings leading from the chamber at a substantial distance below the froth overflow, a second cell of a like construction located at a higher level and a conduit for transferring pulp from the tailings overflow of the lower cell to the inlet opening of the higher cell.

4. A-flotation separation apparatus comprising a cell having a unitary ulp agitatmg and froth separating cham er, an agitator .in the chamber, means for admitting air and pulp to the chamber, a froth separating lip, a pulp exit below the froth level, a second cell located at a higher level and a conduit for conveying the tailings from the pulp exit of the lower cell to the bottom of the agitating and froth separating chamber of the higher cell by the action of gravity alone. p

5. A flotation separation apparatus comprising two cells located adjacent each other and on'difli'erent levels, each cell comprising a unitary pulp agitating and froth separating chamber, a suction agitator in the chamber, means for admitting gas and pulp to the chamber adjacent the center of the agitator, a frothseparating lip, a pulp exit below the froth level, and a conduit leading from the pulp exit of the lower cell to the agitator of the higher cell for conveying the tailings from the chamber of the lower cell to the chamber of the upper cell by the action of gravity alone.

6. An apparatus for froth flotation separation comprising a plurality of cells arranged in an inclined series, each cell of which is on a differente'level than its adjacent cell, each of said cells having a froth separating chamber, means for admitting-gas and pulp to the bottom ofthe chamber, an agitator in the chamber capable of drawing in air and pulp.aga-inst substantially the head of pulp in the chamber, a baflle above the agitator for directing the pulp upwardly from the zone of -agitation, a froth separation lip, a pulp exit below the froth level, means foradjusting the height of said exit and a conduit extending from the pulp exit of a lower cell to the intake of the next higher cell whereby the pulp will be transferred from a lower to a higher cell by the action of gravity. 7

7. A flotation separation apparatus comprising two cells located adjacent each other and on diflerent levels, each cell comprising a unitary pulpagitating and froth separating chamber, a suction agitator in the chamber, means for admitting gas and pulp to the chamber adjacent the center of the agitator, a froth separating lip, a pulp exit below the frothlevel, a conduit leading from the pulp exit of the lower cell to the agitator of the higher cell for conveying the tailings from the chamber. of the lower cell to the chamber of the u per cell, and means for receiving the froth from said cells and for transferring it by the action of gravity alone.

8. An apparatus for froth flotation separation comprlsing a plurality of cells arranged in an inclined series, each cell of which is on a diflerent level than its adjacent cell, each of said cells having a froth separating chamber, means for admitting gas and pulp to the bottom of the chamber, an agitator in the chamber capable of drawing in air and pulp against substantially the head of pulp in the chamber, a bafiie above the a 'tator for directing the pul upwardly mm the zone of agitation, a roth separation lip, a pulp exit below the froth level, means for adjusting the height of said exit, a conduit extending from the pulp exit of a lower cell to the intake of the next higher cell whereby the pulp will be transferred from a lower to a higher cell by the action of gravity and a common launder located below the froth separation lips so as to receive the froth from-the cells, said launder being inclined at such an angle that the froth will flow by the action of gravity alone.

9. A flotation apparatus having a plurality of separate cells each of which 1s located at a different level and adapted to feed one into another by gravity, each of said cells having a feed box and a frothing compartment, the box and compartment being joined by a passageway, an impeller in the passageway, the frothing compartment, having a pulp overflow located above the level of the feed box of the next higher cell, a chute extending from the pulp overflow of each cell to the feed box of the next higher cell, the frothing compartment being also provided with a froth overflow at a higher level than the pulp overflow and an inclined launder extending beneath the froth overflows of the several cells.

10. A flotation apparatus having a plurality of cells each of which is located at a different level than its adjacent cell, each cell having a receiving conduit and a frothin compartment that are in communication wit each other through an opening, means for transferring pulp from the receivin conduit to the frothing compartment and or maintaining the pulp level in the frothing compartment higher than the level in the receiving conduit, the frothing compartment having a pulp overflow and a froth overflow, the pulp overflow being located at a higher level than the receiving conduit of the next higher cell, means for conducting pulp from the pul overflow of each cell to the receiving confluit of the next higher cell and acommon inclined launder extending underneath the froth overflows of the several cells.

In testimony whereof I aflix m si nature.

JOSEPH P. R T ,Jn. 

